Media sanitization (also known as data sanitization) is crucial for organizations
to prevent leakage of confidential and sensitive data from storage media such
as hard drive, USB flash storage, server, etc. Failure to wipe the data when
releasing the storage hardware from custody can expose the company’s sensitive
information and lead to data breach.
standards such as DoD 5220.22-M specify a systematic process for the erasure of
hard drives and other data storage media by defining the overwriting passes,
patterns, and verification methods. The objective of these data wiping standards
is to ensure permanent destruction of data from the storage device, leaving no
traces behind, before device is returned, reallocated, resold, or disposed of
post focuses on the DoD 5220.22-M data wiping standard and how it is used for
getting rid of the unwanted, sensitive data from the storage media.
What is DoD 5220.22-M Standard ?
DoD 5220.22-M, also known as the National Industrial Security
Program Operating Manual or NISPOM, is a
media sanitization standard established by the U.S. Department of Defense. It specifies
the standard procedures and requirements for sanitizing information systems
(i.e., data storage media) that handle classified information. It recommends
overwriting all the addressable memory location with a character, its
complement, then a random character and verify to clear and sanitize the information
on the storage media.
The DoD 5220.22-M Data Wiping Process
The Department of Defense 5220.22-M uses three overwrites passes (0s,
1s, Random) with a 100% verification pass. In 2001, the DoD 5220.22-M ECE
method, a 7-pass version of the standard, was published. It runs DoD 5220.22-M
twice, and an additional pass (DoD 5220.22-M (C) Standard) in between.
Nevertheless, the three-pass method is still its standard implementation. The
DoD 5220.22-M data wipe method involves the following passes:
Pass 1: Writes a zero and verifies the write.
Pass 2: Writes a one and verifies the write.
Pass 3: Writes a random character and verifies the write.
There are other iterations of the DoD standard with
variations in the use of character, its complement (as in zero and one), and
frequencies of verifications. E.g. an altered version of DoD 5220.22-M uses the
number 97 instead of a random character for the last pass.
US Department of Defense 5220.22-M
Clearing and Sanitization Matrix (CSM)
This section presents an outline of the DoD 5220.22-M
specified ‘clear ‘and ‘sanitize’ methods for the different type of storage
media. See the complete grid here.
destroy, or overwrite
remove all power
remove all power, or destroy
then full chip erase or destroy
remove all power
remove all power, or destroy
* Destroy – disintegrate, incinerate,
pulverize, shred, or melt.
** Overwrite – overwrite all addressable
locations with a single character or a single character with complement and
random character and verify.
Full chip erase as per
# EAPROM – Electronically Alterable
PROM; EEPROM – Electronically Erasable PROM
What is the Advantage of The DoD
Over the years, DoD 5220.22 M
standard has established itself as a secure method to erase data from hard disk
drives. It is credible, widely recognized and used in many industries. Though
newer standards like the NIST SP 800-88 have become prevalent for wiping modern
hard drives including flash storage, the DoD 5220.22M still holds credibility
due to its efficiency & assurance.
wiping process runs a three-pass overwrite process for comprehensive yet efficient
wiping as compared to other methods such as the 35-pass Gutmann standard. Its importance
is exemplified if you are trying to erase a large inventory of drives at once. Further,
the verification at the final overwriting pass adds assurance to the data
How to Perform DoD Wiping?
“DoD wiping” means overwriting
all the addressable locations on a hard drive as per the steps specified in the
5220.22-M standard. Professional data erasure software tools such as BitRaser
Drive Eraser can perform DoD wiping. The software allows the users
to select the specific algorithm to overwrite the hard drive storage locations
as per the passes and patterns specified in the DoD 5220.22 standard. It generates
a tamper-proof certificate and report of erasure, which serves as a documented trail
for regulatory compliance.
DoD Wiping – Key Considerations
Here are some essential aspects to
know before choosing DoD 5220.22-M standard as a component of your
organization’s media sanitization strategy:
- DoD 5220.22 does not address wiping of flash
memory-based storage such as solid-state drives (SSDs).
- The NISPOM guideline since 2019 specifies NIST
SP 800-88 as the primary guideline for media sanitization.
- The Department of Defense no longer references
DoD 5220.22 as the method for secure HDD wiping.
- There is no “DoD certification”; however, it is
possible to attain the overwriting process and outcomes as defined in DoD